Displaying publications 81 - 100 of 171 in total

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  1. Kong PS, Pérès Y, Wan Daud WMA, Cognet P, Aroua MK
    Front Chem, 2019;7:205.
    PMID: 31058128 DOI: 10.3389/fchem.2019.00205
    Catalytic esterification of glycerol with oleic acid (OA) was optimized over hydrophobic mesoporous zirconia-silica heterogeneous acid catalyst (ZrO2-SiO2-Me&Et-PhSO3H) and benchmarked with commercial catalysts (Aquivion and Amberlyst 15) in order to examine the effect of catalyst acidity on conversion, yield and product selectivity. The process optimisation results showed an 80% conversion with a 59.4% glycerol mono-oleate (GMO) and 34.6% glycerol dioleate (GDO) selectivities corresponding to a combined GMO and GDO selectivity of 94.8% at equimolar OA-to-glycerol ratio, 160°C reaction temperature, 5 wt% catalyst concentration with respect to the OA weight and 4 h reaction time. This work reveals that the hydrophobic and mild acidic ZrO2-SiO2-Me&Et-PhSO3H catalyst outperformed Amberlyst 15 and Aquivion with a yield of 82% and GMO selectivity of 60%. It is found that catalyst acidity is a key parameter for catalytic activity and conversion rate. Nevertheless, high acidity/acid strength reduced the product yield in the glycerol esterification of OA.
    Matched MeSH terms: Esterification
  2. Jais AM, Matori MF, Kittakoop P, Sowanborirux K
    Gen. Pharmacol., 1998 Apr;30(4):561-3.
    PMID: 9522175
    1. Fatty acid profiles in the external mucus extract and roe of Channa striatus were determined using gas chromatography (GC). 2. The mucus samples were collected by inducing hypothermic stress (-20 degrees C) for about 1 hr, and the roe were collected from gravid females at night soon after they liberated their eggs in a spawning program. 3. All mucus and roe samples were freeze-dried, except a part of roe which was not. 4. The mucus extract contained unsaturated fatty acid (oleic acid, C18:1 and linoleic acid, C18:2) as a major component, 21.25% and 22.47% of total lipid. 5. For the freeze- and nonfreeze-dried roe, the major components of fatty acid were somewhat similar to the mucus but with higher percentages: 58.56%, 26.08% and 45.76%, 20.94%. Interestingly, the nonfreeze-dried roe contained a large proportion of arachidic acid, C20:0 (22.16%), which was totally absent in the freeze-dried roe samples. 6. This profiling of the fatty acid mucus extract and roe is useful in strengthening the earlier claims that haruan possesses a potential remedy for wound healing (Mat Jais et al., 1994). Therefore, we are discussing the possibility of getting an optimum amount of the essential fatty acid for wound healing from various other parts of the fish without sacrificing the fish.
    Matched MeSH terms: Esterification
  3. Nazaruddin, R., Noor Baiti, A.A., Foo, S.C., Tan, Y.N., Ayob, M.K.
    MyJurnal
    Recent research suggesting the existence of potential source of pectin from roselle calyces. Pectin was successfully extracted from seven different varieties of roselle calyces. Pectin extraction was conducted using hydrochloric acid (HCl, 0.03 N, pH 1.5) or ammonium oxalate (0.25% w/v, pH 4.6) at 85⁰C for 1 h. Chemical characteristics of the HCl- and ammonium oxalate extracted pectin were compared. Results indicated that ammonium oxalate exhibited greater efficiency in pectin extraction than HCl. Highest pectin yield at 18.7% was obtained by ammonium oxalate extraction of roselle calyx variety Acc.6 compared to only 9.77% by HCl extraction. The lowest pectin yield at 11.3% and 5.78% were observed respectively in ammonium oxalate and HCl extractions of roselle calyx variety UKMR-3. Some important characteristics of ammonium oxalate extracted pectin of roselle Acc.6 were 5.98% moisture, 3.81% ash, 4.64% methoxyl content, 42.24% anhydrouronic acid (AUA) and degree of esterification (DE) 60%. This study suggested that the high DE% roselle pectin is an alternative source of pectin for food industry.
    Matched MeSH terms: Esterification
  4. Zarei, M., Ahmadi Zenouz, A., Saari, N., Ghanbari, R., Nikkhah, M., Vaziri, M.
    MyJurnal
    Microwave assisted extraction treatments showed the higher pectin yields of 10.07% and 8.83% in pretreated samples by microwave and 9.4% and 8% in the extraction of dried after microwave treatment in lemon peel and apple pomace samples, respectively. Lemon peel pectin in pretreated samples by microwave and extraction of dried after microwave treatment showed the higher degree of esterification 71.8% and 70%, respectively, while apple pomace revealed 68% and 65.4% in same treatments. Furthermore, lemon peel pectin exhibited the highest galacturonic content of 74.5% in extraction of pretreated samples by microwave, while apple pomace pectin indicated the higher galacturonic acid content of 70.5% and 70% in both extraction of dried after microwave treatment and extraction of dried samples. Texture analysis of jellies prepared by various extracted pectin indicated the highest fracturability in the microwave-assisted drying treatment of 33 N and 32.5 N for apple pomace and lemon peel pectin, respectively.
    Matched MeSH terms: Esterification
  5. Zainal Abidin, N.F., Yusoff, A., Ahmad, N.
    MyJurnal
    Octenyl succinic anhydride (OSA) modified sago starch was prepared in order to improve the emulsification properties of native starch. In the present study, the major factors affecting esterification were investigated with respect to OSA concentration, pH and reaction time using response surface methodology (RSM) based on central composite rotatable design (CCRD) to obtain the highest value of degree of substitution (DS). Results shown that the optimum conditions for OSA concentration, pH and reaction time were 5.00%, pH 7.20 and 9.65 h, respectively. At optimum condition, the esterification of sago starch with OSA resulted in DS value of 0.0120. The DS increased linearly with the increase in amount of OSA, whilst pH and reaction time show a curvature trend on the value of DS. The value of DS was found to be significantly affected by all the three variables. The experimental values under optimum condition were in good consistent with the predicted values (0.0131), which suggested that the optimisation by RSM is more efficient process than conventional optimisation.
    Matched MeSH terms: Esterification
  6. Nur Farhana A.R., Amin I., Sadeq Hassan A.S., Shuhaimi M.
    MyJurnal
    Okra plant particularly its fruit is highly mucilage which composed of pectin and high content of carbohydrate. Byproducts of okra plant such as leaves and matured fruits will be discarded whenever the young fruits are harvested which eventually leads to environmental pollution. Those byproducts have potential to become plant-based alternative for bovine and pork related gelatin. This study aimed to determine the gel formation of pectin extracted from okra plant byproducts particularly the leaves, pulp (skin without seeds) and seeds. Pectin was extracted using a sequential extraction with the applications of hot buffer (HB) and hot buffer with chelating agents (CH). CH extraction gave the highest pectin yield (>40%) compared to HB and DA. The HB fraction harbored highly purified pectin due to high anhydro uronic acid content and degree of esterification. The highest pectin yield was extracted from seeds with an overall fraction yield of 86%, followed by the leaves (75%) and pulp (71%). The pectin was blended with konjac glucomannan (KG) in 5.0:1.6 ratio to form gel and stored for 16 - 18hr at 4°C ± 1.0. The gel formed using HB extraction was found to have significantly lower (p < 0.05) gel strength than HB with CH extraction. This study concluded that HB and CH pectin extracts derived from okra leaves, pulp and seeds have good potential to become gelling agent.
    Matched MeSH terms: Esterification
  7. Kamarudin F, Gan CY
    Int J Biol Macromol, 2016 Jul;88:280-7.
    PMID: 27044345 DOI: 10.1016/j.ijbiomac.2016.04.003
    Pinto bean pod polysaccharide (PBPP) was successfully extracted with yield of 38.5g/100g and the PBPP gave total carbohydrate and uronic acid contents of 286.2mg maltose equivalent/g and 374.3mgGal/g, respectively. The Mw of PBPP was 270.6kDa with intrinsic viscosity of 0.262dm(3)/g, which composed of mannose (2.5%), galacturonic acid (15.0%), rhamnose (4.0%), glucose (9.0%), galactose (62.2%), xylose (2.9%) and arabinose (4.3%) with trace amount of ribose and fucose. The result suggested that PBPP has a spherical conformation with a highly branched structure. Fourier Transform Infrared analysis showed that PBPP has a similar structure as commercial pectin with an esterification degree of 59.9%, whereas scanning electron microscopy study showed that the crude polysaccharide formed a thin layer of film that was made of multiple micro strands of fibre. PBPP exhibited substantial free radical scavenging activity (7.7%), metal reducing capability (2.04mmol/dm(3)) and α-amylase inhibitory activity (97.6%) at a total amount of 1mg. PBPP also exhibited high water- and oil-holding capacities (3.6g/g and 2.8g/g, respectively). At a low concentration, PBPP exhibited emulsifying activity of 39.6% with stability of 38.6%. Apart from that, PBPP was able to show thickening capability at low concentration (0.005kg/dm(3)).
    Matched MeSH terms: Esterification
  8. Tan HF, Gan CY
    Int J Biol Macromol, 2016 Apr;85:487-96.
    PMID: 26778156 DOI: 10.1016/j.ijbiomac.2016.01.023
    Functional polysaccharide was isolated from Momordica charantia, with a yield of 36% (w/w). M. charantia bioactive polysaccharide (MCBP) was an acidic and branched heteropolysaccharide with a molecular weight of 92 kDa. Fourier transform infrared spectroscopic analysis indicated that MCBP was a pectin-like polysaccharide with an esterification degree of 53% and it contains numerous monosaccharides, predominantly glucose, galactose, and galaturonic acid. The results also showed that MCBP exhibited free radical scavenging activity (31.9%), ferric reducing antioxidant power (0.95 mM), α-amylase inhibition (89.1%), and angiotensin-converting enzyme inhibition (94.1%). In the terms of functionality, MCBP showed a lower water-holding capacity but higher in oil-holding capacity, emulsifying activity and foaming capacity compared to citrus pectin. Scanning electron microscopy images demonstrated that MCBP formed gels with a porous structure, and flow analysis showed that the gel solution exhibited pseudoplastic shear-thinning behavior. These findings indicated that MCBP is a promising functional macromolecular carbohydrate for the food and nutraceutical industries.
    Matched MeSH terms: Esterification
  9. Zaid RM, Mishra P, Tabassum S, Wahid ZA, Sakinah AMM
    Int J Biol Macromol, 2019 Dec 01;141:1147-1157.
    PMID: 31494156 DOI: 10.1016/j.ijbiomac.2019.09.017
    The effect of physicochemical treatment on pectin yield, degree of esterification, along with the kinetics and thermodynamics characteristics was investigated in the present study. Several extraction parameters were observed to have impacted the yield and degree of esterification significantly, and the best extraction condition was as follows: agitation rate of 250 rpm, temperature of 70 °C, extraction time of 120 min, pH 2, and liquid to solid ratio of 10 v/w which has resulted in 28.20% of pectin yield, with DE (degree of esterification) of 57.00%. A theoretical model which describes the extractability, dissolution and degradation rate of pectin to predict the maximal yield at the maximal time was established to study the extraction kinetics of pectin from HPP. The kinetic analysis from Panchev's model shows the extraction rate was found highest at LSR 10 with ymax 30.85%. The calculated activation energy for pectin dissolution and degradation was found to be 4.532 kJ/mol and 28.054 kJ/mol, respectively. The thermodynamic study has suggested that the process was endothermic, spontaneous and reversible. These results suggest that the physical and chemical treatment applied could be an efficient technique for the extraction of pectin from Hylocereus polyrhizus peels.
    Matched MeSH terms: Esterification
  10. Zaid RM, Mishra P, Wahid ZA, Sakinah AMM
    Int J Biol Macromol, 2019 Aug 01;134:361-367.
    PMID: 31059740 DOI: 10.1016/j.ijbiomac.2019.03.143
    In the present study, high-methoxyl pectin (HMP) was extracted from Hylocereus polyrhizus peel's using physico-chemical process. In addition, the hypolipidemic activity of HMP was investigated at different concentration and time corresponding to its adsorption ability. FTIR and contact angle analysis were used to determine the sorbent characterization. A high degree of esterification (63.8%) and the contact angle (95.5°) confirmed hydrophobic nature and resulting bad wetting of the HMP extract, respectively. The methoxyl content in the pectin acted as an affinity-precursor of the pectin towards cholesterol due to its increased hydrophobicity. The maximum equilibrium uptake capacity of cholesterol of 370.5mg/g (0.96mmol/g) was observed by HMP. The experimental data showed good fitting for Freundlich isotherm equation and followed pseudo-first-order kinetic model with a correlation coefficient (R2) of 0.89-0.97 due to physisorption mechanism. Intra-particle model confirmed that the cholesterol sorption rate by HMP was significantly influenced by external mass transfer (surface diffusion) and intra-particle diffusion (diffusion control). It was also revealed that the HMP extracted from Hylocereus polyrhizus peels possess a high affinity towards cholesterol, making it an ideal hypolipidemic agent.
    Matched MeSH terms: Esterification
  11. Abdul Hadi N, Marefati A, Purhagen J, Rayner M
    Int J Biol Macromol, 2024 May;267(Pt 1):131523.
    PMID: 38608987 DOI: 10.1016/j.ijbiomac.2024.131523
    Rice and quinoa starches are modified with short-chain fatty acids (SCFA) with different SCFA acyl chain lengths and levels of modification. This work is aimed to investigate the impact of modifying rice and quinoa starches with short-chain fatty acids (SCFAs) on various physicochemical properties, including particle size, protein and amylose content, thermal behavior, pasting characteristics, and in vitro digestibility. Both native and SCFA-starches showed comparable particle sizes, with rice starches ranging from 1.58 to 2.22 μm and quinoa starches from 5.18 to 5.72 μm. SCFA modification led to lower protein content in both rice (0.218-0.255 %) and quinoa starches (0.537-0.619 %) compared to their native counterparts. Esterification led to the reduction of gelatinization and pasting temperatures as well as the hardness of the paste of SCFA-starches were reduced while paste clarity increased. The highest level of modification in SCFA-starch was associated with the highest amount of resistant starch fraction. Principal component analysis revealed that modification levels exerted a greater influence on starch properties than the types of SCFA used (acetyl, propionyl, and butyryl). These findings is importance in considering the degree of substitution or level of modification when tailoring starch properties through SCFA modification, with implications for various applications in food applications.
    Matched MeSH terms: Esterification
  12. Wahab RA, Basri M, Rahman MB, Rahman RN, Salleh AB, Leow TC
    Int J Mol Sci, 2012;13(9):11666-80.
    PMID: 23109876 DOI: 10.3390/ijms130911666
    The substitution of the oxyanion Q114 with Met and Leu was carried out to investigate the role of Q114 in imparting enantioselectivity on T1 lipase. The mutation improved enantioselectivity in Q114M over the wild-type, while enantioselectivity in Q114L was reduced. The enantioselectivity of the thermophilic lipases, T1, Q114L and Q114M correlated better with log p as compared to the dielectric constant and dipole moment of the solvents. Enzyme activity was good in solvents with log p < 3.5, with the exception of hexane which deviated substantially. Isooctane was found to be the best solvent for the esterification of (R,S)-ibuprofen with oleyl alcohol for lipases Q114M and Q114L, to afford E values of 53.7 and 12.2, respectively. Selectivity of T1 was highest in tetradecane with E value 49.2. Solvents with low log p reduced overall lipase activity and dimethyl sulfoxide (DMSO) completely inhibited the lipases. Ester conversions, however, were still low. Molecular sieves employed as desiccant were found to adversely affect catalysis in the lipase variants, particularly in Q114M. The higher desiccant loading also increased viscosity in the reaction and further reduced the efficiency of the lipase-catalyzed esterifications.
    Matched MeSH terms: Esterification
  13. Siyamak S, Ibrahim NA, Abdolmohammadi S, Yunus WM, Rahman MZ
    Int J Mol Sci, 2012;13(2):1327-46.
    PMID: 22408394 DOI: 10.3390/ijms13021327
    A new class of biocomposites based on oil palm empty fruit bunch fiber and poly(butylene adipate-co-terephthalate) (PBAT), which is a biodegradable aliphatic aromatic co-polyester, were prepared using melt blending technique. The composites were prepared at various fiber contents of 10, 20, 30, 40 and 50 wt% and characterized. Chemical treatment of oil palm empty fruit bunch (EFB) fiber was successfully done by grafting succinic anhydride (SAH) onto the EFB fiber surface, and the modified fibers were obtained in two levels of grafting (low and high weight percentage gain, WPG) after 5 and 6 h of grafting. The FTIR characterization showed evidence of successful fiber esterification. The results showed that 40 wt% of fiber loading improved the tensile properties of the biocomposite. The effects of EFB fiber chemical treatments and various organic initiators content on mechanical and thermal properties and water absorption of PBAT/EFB 60/40 wt% biocomposites were also examined. The SAH-g-EFB fiber at low WPG in presence of 1 wt% of dicumyl peroxide (DCP) initiator was found to significantly enhance the tensile and flexural properties as well as water resistance of biocomposite (up to 24%) compared with those of untreated fiber reinforced composites. The thermal behavior of the composites was evaluated from thermogravimetric analysis (TGA)/differential thermogravimetric (DTG) thermograms. It was observed that, the chemical treatment has marginally improved the biocomposites' thermal stability in presence of 1 wt% of dicumyl peroxide at the low WPG level of grafting. The improved fiber-matrix surface enhancement in the chemically treated biocomposite was confirmed by SEM analysis of the tensile fractured specimens.
    Matched MeSH terms: Esterification
  14. Abdulkarim MF, Abdullah GZ, Chitneni M, Salman IM, Ameer OZ, Yam MF, et al.
    Int J Nanomedicine, 2010 Nov 04;5:915-24.
    PMID: 21116332 DOI: 10.2147/IJN.S13305
    INTRODUCTION: During recent years, there has been growing interest in use of topical vehicle systems to assist in drug permeation through the skin. Drugs of interest are usually those that are problematic when given orally, such as piroxicam, a highly effective anti-inflammatory, anti-pyretic, and analgesic, but with the adverse effect of causing gastrointestinal ulcers. The present study investigated the in vitro and in vivo pharmacodynamic activity of a newly synthesized palm oil esters (POEs)-based nanocream containing piroxicam for topical delivery.

    METHODS: A ratio of 25:37:38 of POEs: external phase: surfactants (Tween 80:Span 20, in a ratio 80:20), respectively was selected as the basic composition for the production of a nanocream with ideal properties. Various nanocreams were prepared using phosphate-buffered saline as the external phase at three different pH values. The abilities of these formulae to deliver piroxicam were assessed in vitro using a Franz diffusion cell fitted with a cellulose acetate membrane and full thickness rat skin. These formulae were also evaluated in vivo by comparing their anti-inflammatory and analgesic activities with those of the currently marketed gel.

    RESULTS: After eight hours, nearly 100% of drug was transferred through the artificial membrane from the prepared formula F3 (phosphate-buffered saline at pH 7.4 as the external phase) and the marketed gel. The steady-state flux through rat skin of all formulae tested was higher than that of the marketed gel. Pharmacodynamically, nanocream formula F3 exhibited the highest anti- inflammatory and analgesic effects as compared with the other formulae.

    CONCLUSION: The nanocream containing the newly synthesized POEs was successful for trans-dermal delivery of piroxicam.

    Matched MeSH terms: Esterification
  15. Noraini Hamzah, Izyan Yusof, Sabiha Hanim Saleh, Nazrizawati Ahmad Tajuddin, Mohd Lokman Ibrahim, Wan Zurina Samad
    MyJurnal
    Demand for diesel continues to increase due to rapid population growth, which could contribute to fossil fuel exhaustion. Biodiesel has been widely developed as a replacement for conventional diesel to resolve the issue. Biodiesel production from waste cooking oil (WCO) was carried out via the transesterification process using two types of bentonite catalysts, which are raw bentonite and NaOH/bentonite. By using the impregnation method, the NaOH/bentonite catalyst was synthesized at 60°C for 12 hours. The transesterification was conducted with 0.5wt% of catalyst, at 15:1 (methanol- to-oil), for 2 hours at different reaction temperatures. The characterization of both raw bentonite and NaOH/bentonite was done using X-ray Diffraction (XRD) and Brunauer, Emmett, Teller (BET) surface characterization. A high yield of FAMEs (72%) was found to be obtained in continuous stirring at 55ºC for 2 hours and 15:1 methanol/oil molar ratio with 0.5wt.% (0.15g) of NaOH/bentonite catalyst.
    Matched MeSH terms: Esterification
  16. Wahab Abideen Akinkunmi, Awang Ahmad Sallehin Awang Husaini, Azham Zulkharnain, Tay, Meng Guan, Hairul Azman Roslan
    MyJurnal
    Filamentous fungi such as Fusarium equiseti KR706303 and Penicillium citrinum KR706304
    are capable of sequestering heavy metals from aqueous solutions. In the present study, the role
    play by various functional groups present in the cell wall of F. equiseti KR706303 and P.
    citrinum KR706304 during lead and copper ions biosorption was investigated. The fungal
    biomass was chemically treated to modify the functional groups present in their cell wall. These
    modifications were studied through biosorption experiments. It was found that an esterification
    of the carboxyl and phosphate groups, methylation of the amine groups and extraction of lipids
    significantly decrease the biosorption of both lead and copper ions studied. Therefore, the
    carbonyl, hydroxyl and amide groups were recognized as important in the biosorption of metal
    ions by the tested fungi. The study showed that there was no release of any metal ions from the
    biomass after biosorption, indicating that ion exchange may not be a key mechanism in the
    biosorption of lead and copper ions by these fungi but complexation of metal ions within the
    fungal cell wall.
    Matched MeSH terms: Esterification
  17. Tevan, R., Jayakumar, Saravanan, Mohd Hasbi Ab. Rahim, Maniam, Gaaty Pragas, Govindan, Natanamurugaraj
    MyJurnal
    The world is facing a problem regarding the use of petroleum fuels that has led to a search for a suitable alternative fuel source. Researchers have come up with the idea of producing biofuel to overcome this problem. In this study, microalgae were explored as a high potential feedstock to produce biofuel. In order to produce a large quantity of biofuel with low cost at a short time, the manipulation of nutrients is a factor in microalgae cultivation. In this study, Iron (II) Chloride (FeCl2) was added to the nutrients to initiate a stressful condition during growth which contributes to the produce of lipid. Isolated microalgae species were identified as Scenedesmus sp. During mass cultivation, the microalgae cultures were scaled up to 2 L of culture. Three flasks of microalgae culture were labelled with S1, S2, and S3. Flask S1 acts as a control without the addition of FeCl2, while another two flasks acted as experimental flasks. Flask S2 was supplemented with 0.5 mg FeCl2 while Flask S3 was supplemented with 1.0 mg of FeCl2. With the addition of Iron (II) Chloride, microalgae entered a stationary phase at day 9 and day 10 as compared to the control flask which enters the stationary phase at day 7. This also affects the dry weight. Flask 3 produces 0.8658 g of microalgae powder compared to Flask 1 and 2 which produced 0.4649 g and 0.5357 g respectively. Lipid analysis was done by using GCMS and GCFID. Flask 3 produced various types of fatty acids which can be used for biodiesel production compared to other cultivates. In Flask 1, docosanoic acid which is a saturated fatty acid was detected. While in Flask 2 (S2), with the addition of 0.5 mg of FeCl2, docosapentaenoic acid was produced. In the last flask which involved the addition of 1.0 mg of FeCl2, more fatty acid was detected. In GC-FID data, 6 types of fatty acids were detected. Linolein acid, linolenic acid, stearidonic acid, docosapentaenoic acid, docosahexaenoic acid and docosanoic acid were produced at different retention times. Most of the fatty acids produced are polyunsaturated fatty acid (PUFA). In transesterification, the fatty acid reacts with methanol and acid catalyst. The reaction produces fatty acid methyl ester. In Flask 1, the control flask, without the addition of FeCl2, no fatty acid methyl esters (FAME) was produced. However, in Flask 2 and 3 which were added 0.5 mg FeCl2 and 1.0 mg FeCl2, n-hexadecanoic acid methyl ester which is also known as palmitic acid was produced. Palmitic fatty acid can be used for biodiesel production.
    Matched MeSH terms: Esterification
  18. Leman, A.M., Amir Khalid, Dafit Feriyanto, Abdullah, N.H., Abdullah, A.A., Mamat, R.
    MyJurnal
    In this research, the biodiesel from WCO is used in order to reduce the exhaust emission and to investigate the
    community perception regarding to the human health. Biodiesel production is conducted using trans-esterification
    process with holding time of 2 hours, temperature of 60 oC and conventional frequency of 20 kHz and then followed
    by washing process with holding time of 1 hours, temperature of 50 oC and the frequency of 5 kHz. Biodiesel can
    reduce exhaust emission of NOx up to 55%, NO gas up to 57%, increase CO gas up to 25% and increase CO2 gas up
    to 43.18% as compared to diesel fuel. In addition, biodiesel is achieve good responds from 35 respondents about the
    biodiesel importance.
    Matched MeSH terms: Esterification
  19. Lo SK, Cheong LZ, Arifin N, Tan CP, Long K, Yusoff MS, et al.
    J Agric Food Chem, 2007 Jul 11;55(14):5595-603.
    PMID: 17571899
    Diacylglycerol (DAG) and triacylglycerol (TAG) as responses on optimization of DAG production using a dual response approach of response surface methodology were investigated. This approach takes the molecular equilibrium of DAG into account and allows for the optimization of reaction conditions to achieve maximum DAG and minimum TAG yields. The esterification reaction was optimized with four factors using a central composite rotatable design. The following optimized conditions yielded 48 wt % DAG and 14 wt % TAG: reaction temperature of 66.29 degrees C, enzyme dosage of 4 wt %, fatty acid/glycerol molar ratio of 2.14, and reaction time of 4.14 h. Similar results were achieved when the process was scaled up to a 10 kg production in a pilot packed-bed enzyme reactor. Lipozyme RM IM did not show any significant activity losses or changes in fatty acid selectivity on DAG synthesis during the 10 pilot productions. However, lipozyme RM IM displayed higher selectivity toward the production of oleic acid-enriched DAG. The purity of DAG oil after purification was 92 wt %.
    Matched MeSH terms: Esterification
  20. Musa H, Hafiz Kasim F, Nagoor Gunny AA, Gopinath SCB, Azmier Ahmad M
    J Basic Microbiol, 2019 Jan;59(1):87-100.
    PMID: 30270443 DOI: 10.1002/jobm.201800382
    An approach was made to enhance the halophilic lipase secretion by a newly isolated moderate halophilic Marinobacter litoralis SW-45, through the statistical optimization of Plackett-Burman (PB) experimental design and the Face Centered Central Composite Design (FCCCD). Initially, PB statistical design was used to screen the medium components and process parameters, while the One-factor-at-a-time technique was availed to find the optimum level of significant parameters. It was found that MgSO4  · 7H2 O, NaCl, agitation speed, FeSO4  · 7H2 O, yeast extract and KCl positively influence the halophilic lipase production, whereas temperature, carbon source (maltose), inducer (olive oil), inoculum size, and casein-peptone had a negative effect on enzyme production. The optimum level of halophilic lipase production was obtained at 3.0 g L-1 maltose, 1% (v/v) olive oil, 30 °C growth temperature and 4% inoculum volume (v/v). Further optimization by FCCCD was revealed 1.7 folds improvement in the halophilic lipase production from 0.603 U ml-1 to 1.0307 U ml-1 . Functional and biochemical characterizations displayed that the lipase was significantly active and stable in the pH ranges of 7.0-9.5, temperature (30-50 °C), and NaCl concentration (0-21%). The lipase was maximally active at pH 8.0, 12% (w/v) NaCl, and 50 °C temperature. Besides, M. litoralis SW-45 lipase was found to possess the promising industrial potential to be utilized as a biocatalyst for the esterification.
    Matched MeSH terms: Esterification
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